low-fat diet and/or flaxseed in preventing prostate cancer

Conditions: Prostate Cancer

Summary: rationale: a diet that is low in fat and/or high in flaxseed may slow or prevent disease progression of prostate cancer. purpose: randomized phase ii trial to study the effectiveness of a diet that is low in fat and/or high in flaxseed in slowing or preventing disease progression in patients who have newly diagnosed prostate cancer.

objectives: * compare tumor proliferation in patients with newly diagnosed prostate cancer eating fat- and/or flaxseed-modified diets. * compare differences in histopathological markers associated with prostate cancer (rates of apoptosis, extent of high-grade prostatic intraepithelial neoplasia) among patients in these diet groups. * compare changes in serum prostate specific antigen among patients in these diet groups. * compare changes in hormone-related factors (total serum testosterone and free androgen index, insulin-like growth factor \[igf\], and igf-binding protein-3) among patients in these diet groups. * compare the effects of diet on nutritional biomarkers (levels of lignans in the urine and ejaculate, fatty acid profiles of erythrocytes and prostatic tissue) in these patients. * determine associations between dietary modification and changes in dietary biomarkers, hormonal intermediates, and study endpoints in these patients. outline: this is a randomized study. patients are stratified according to gleason score (less than 7 vs at least 7) and race (black vs non-black). patients are randomized to 1 of 4 diet groups. * arm i (flaxseed-supplemented diet): patients are instructed to incorporate ground flaxseed into their daily diets. * arm ii (low-fat diet): patients are instructed on ways to achieve a diet with no greater than 20% of total energy from dietary fat. * arm iii (flaxseed-supplemented, low-fat diet): patients are instructed as in arm i and arm ii. * arm iv (control diet): patients are contacted weekly, but do not receive dietary counseling until after surgery. all patients ingest the diets for at least 3 weeks and complete diet diaries until surgery. after surgery, all patients receive dietary counseling. projected accrual: a total of 160 patients (40 per treatment arm) will be accrued for this study.

Eligibility criteria:
disease characteristics: * histologically confirmed prostate cancer * at least 3 weeks until planned prostatectomy (24 days between day 1 visit and surgery) * current diet that provides more than 30% of calories from fat patient characteristics: age * 18 and over performance status * not specified life expectancy * not specified hematopoietic * not specified hepatic * not specified renal * not specified other * mentally competent * able to speak and write english * must have telephone access prior concurrent therapy: biologic therapy * not specified chemotherapy * not specified endocrine therapy * no concurrent hormonal therapy radiotherapy * not specified surgery * at least 2 weeks since prior prostate biopsy other * at least 7 days since prior antibiotics * no prior therapy for prostate cancer * no concurrent dietary supplements initiated within the past 3 months or anticipated to begin during study except standard multivitamin/mineral preparations (e.g., one-a-day, theragran, or centrum) that do not supply \> 100% of the recommended daily allowance of any vitamin or mineral * no other concurrent neoadjuvant therapies * no other concurrent flaxseed consumption

Keywords: stage i prostate cancer stage iib prostate cancer stage iia prostate cancer stage iii prostate cancer